import { IUseCase } from '../../../core/application/IUseCase';
import { Result } from '../../../core/domain/Result';
import { DomainError, ValidationError } from '../../../core/domain/DomainError';
import { IListRepository } from '../domain/IListRepository';
import { NoteList } from '../domain/NoteList';
import { ListItem } from '../domain/ListItem';
import { AddListItemDto } from './dtos/ListDtos';

export class AddListItemUseCase implements IUseCase<AddListItemDto, ListItem> {
  constructor(private readonly listRepository: IListRepository) {}

  public async execute(dto: AddListItemDto): Promise<Result<ListItem, DomainError>> {
    if (!dto.title || dto.title.trim().length === 0) {
      return Result.fail(new ValidationError('Item title is required'));
    }

    if (!dto.ownerId) {
      return Result.fail(new ValidationError('Owner ID is required'));
    }

    let targetList: NoteList | null = null;

    if (dto.listId) {
      targetList = await this.listRepository.findListById(dto.listId);
    } else if (dto.listTitle) {
      targetList = await this.listRepository.findListByTitleAndOwner(dto.listTitle.trim(), dto.ownerId);
    }

    // Если список не найден по названию (например, первая запись фильма), создаем список автоматически
    if (!targetList) {
      const listTitle = dto.listTitle?.trim() || 'Общий список';
      const category = dto.category || (listTitle.toLowerCase().includes('фильм') ? 'movies' : 'general');
      
      targetList = new NoteList({
        id: `list-${Date.now()}-${Math.random().toString(36).substr(2, 6)}`,
        title: listTitle,
        category: category,
        description: `Автоматически создан для ${listTitle}`,
        ownerId: dto.ownerId,
        createdAt: new Date(),
        updatedAt: new Date(),
        items: []
      });

      await this.listRepository.saveList(targetList);
    }

    const newItem = new ListItem({
      id: `item-${Date.now()}-${Math.random().toString(36).substr(2, 6)}`,
      listId: targetList.id,
      title: dto.title.trim(),
      description: dto.description || '',
      isCompleted: false,
      status: targetList.category === 'movies' ? 'want_to_watch' : 'todo',
      priority: dto.priority || 'normal',
      metadata: dto.metadata || {},
      dueDate: null,
      createdAt: new Date(),
      updatedAt: new Date()
    });

    await this.listRepository.saveItem(newItem);
    targetList.addItem(newItem);

    return Result.ok(newItem);
  }
}